<?php
/**
 * CodeIgniter
 *
 * An open source application development framework for PHP
 *
 * This content is released under the MIT License (MIT)
 *
 * Copyright (c) 2014 - 2015, British Columbia Institute of Technology
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 *
 * @package    CodeIgniter
 * @author    EllisLab Dev Team
 * @copyright    Copyright (c) 2008 - 2014, EllisLab, Inc. (http://ellislab.com/)
 * @copyright    Copyright (c) 2014 - 2015, British Columbia Institute of Technology (http://bcit.ca/)
 * @license    http://opensource.org/licenses/MIT    MIT License
 * @link    http://codeigniter.com
 * @since    Version 3.0.0
 * @filesource
 */
defined('BASEPATH') OR exit('No direct script access allowed');

/**
 * Interbase/Firebird Forge Class
 *
 * @category    Database
 * @author        EllisLab Dev Team
 * @link        http://codeigniter.com/user_guide/database/
 */
class CI_DB_ibase_forge extends CI_DB_forge {

    /**
     * CREATE TABLE IF statement
     *
     * @var    string
     */
    protected $_create_table_if    = FALSE;

    /**
     * RENAME TABLE statement
     *
     * @var    string
     */
    protected $_rename_table    = FALSE;

    /**
     * DROP TABLE IF statement
     *
     * @var    string
     */
    protected $_drop_table_if    = FALSE;

    /**
     * UNSIGNED support
     *
     * @var    array
     */
    protected $_unsigned        = array(
        'SMALLINT'    => 'INTEGER',
        'INTEGER'    => 'INT64',
        'FLOAT'        => 'DOUBLE PRECISION'
    );

    /**
     * NULL value representation in CREATE/ALTER TABLE statements
     *
     * @var    string
     */
    protected $_null        = 'NULL';

    // --------------------------------------------------------------------

    /**
     * Create database
     *
     * @param    string    $db_name
     * @return    string
     */
    public function create_database($db_name)
    {
        // Firebird databases are flat files, so a path is required

        // Hostname is needed for remote access
        empty($this->db->hostname) OR $db_name = $this->hostname.':'.$db_name;

        return parent::create_database('"'.$db_name.'"');
    }

    // --------------------------------------------------------------------

    /**
     * Drop database
     *
     * @param    string    $db_name    (ignored)
     * @return    bool
     */
    public function drop_database($db_name = '')
    {
        if ( ! ibase_drop_db($this->conn_id))
        {
            return ($this->db->db_debug) ? $this->db->display_error('db_unable_to_drop') : FALSE;
        }
        elseif ( ! empty($this->db->data_cache['db_names']))
        {
            $key = array_search(strtolower($this->db->database), array_map('strtolower', $this->db->data_cache['db_names']), TRUE);
            if ($key !== FALSE)
            {
                unset($this->db->data_cache['db_names'][$key]);
            }
        }

        return TRUE;
    }

    // --------------------------------------------------------------------

    /**
     * ALTER TABLE
     *
     * @param    string    $alter_type    ALTER type
     * @param    string    $table        Table name
     * @param    mixed    $field        Column definition
     * @return    string|string[]
     */
    protected function _alter_table($alter_type, $table, $field)
     {
        if (in_array($alter_type, array('DROP', 'ADD'), TRUE))
        {
            return parent::_alter_table($alter_type, $table, $field);
        }

        $sql = 'ALTER TABLE '.$this->db->escape_identifiers($table);
        $sqls = array();
        for ($i = 0, $c = count($field); $i < $c; $i++)
        {
            if ($field[$i]['_literal'] !== FALSE)
            {
                return FALSE;
            }

            if (isset($field[$i]['type']))
            {
                $sqls[] = $sql.' ALTER COLUMN '.$this->db->escape_identififers($field[$i]['name'])
                    .' TYPE '.$field[$i]['type'].$field[$i]['length'];
            }

            if ( ! empty($field[$i]['default']))
            {
                $sqls[] = $sql.' ALTER COLUMN '.$this->db->escape_identifiers($field[$i]['name'])
                    .' SET DEFAULT '.$field[$i]['default'];
            }

            if (isset($field[$i]['null']))
            {
                $sqls[] = 'UPDATE "RDB$RELATION_FIELDS" SET "RDB$NULL_FLAG" = '
                    .($field[$i]['null'] === TRUE ? 'NULL' : '1')
                    .' WHERE "RDB$FIELD_NAME" = '.$this->db->escape($field[$i]['name'])
                    .' AND "RDB$RELATION_NAME" = '.$this->db->escape($table);
            }

            if ( ! empty($field[$i]['new_name']))
            {
                $sqls[] = $sql.' ALTER COLUMN '.$this->db->escape_identifiers($field[$i]['name'])
                    .' TO '.$this->db->escape_identifiers($field[$i]['new_name']);
            }
        }

        return $sqls;
     }

    // --------------------------------------------------------------------

    /**
     * Process column
     *
     * @param    array    $field
     * @return    string
     */
    protected function _process_column($field)
    {
        return $this->db->escape_identifiers($field['name'])
            .' '.$field['type'].$field['length']
            .$field['null']
            .$field['unique']
            .$field['default'];
    }

    // --------------------------------------------------------------------

    /**
     * Field attribute TYPE
     *
     * Performs a data type mapping between different databases.
     *
     * @param    array    &$attributes
     * @return    void
     */
    protected function _attr_type(&$attributes)
    {
        switch (strtoupper($attributes['TYPE']))
        {
            case 'TINYINT':
                $attributes['TYPE'] = 'SMALLINT';
                $attributes['UNSIGNED'] = FALSE;
                return;
            case 'MEDIUMINT':
                $attributes['TYPE'] = 'INTEGER';
                $attributes['UNSIGNED'] = FALSE;
                return;
            case 'INT':
                $attributes['TYPE'] = 'INTEGER';
                return;
            case 'BIGINT':
                $attributes['TYPE'] = 'INT64';
                return;
            default: return;
        }
    }

    // --------------------------------------------------------------------

    /**
     * Field attribute AUTO_INCREMENT
     *
     * @param    array    &$attributes
     * @param    array    &$field
     * @return    void
     */
    protected function _attr_auto_increment(&$attributes, &$field)
    {
        // Not supported
    }

}
